Bamboo belongs to Bambusoideae family in Gramineae. There are about 70 genera, over 1200 species of bamboo on the earth. The area of bamboo grove is approximately 20,000,000 hectare all over the world. China is one of main bamboo producing countries in the world. In China, there are about 40 genera, over 400 species of bamboo (i.e. one-third of world bamboo resources) and the area of bamboo grove is approximately 4,000,000 hectare. Meanwhile, there are over 50 species of bamboo in Phyllostachys Sieb. et Zucc all over the world. Many species of them have been produced in China except minority varieties. Furthermore, the area of bamboo in Phyllotachys pubescens, which has the highest economic utility value in bamboo kingdom, is about 2,500,000 hectare (i.e. more than 90% of world bamboo yields in Phyllotachys pubescens) in China.
Bamboo is one of the most valuable natural plants all over the world. Bamboo is praised as “Gold of the Poor” for its high economic value so that it acts as an important ingredient of forest resources. Meanwhile, bamboo has widespread ecological environmental effects and social benefits. Researches on the available compositions and biological effects of bamboo are mainly in China and Japan. Besides, a few of similar researches are conducted in India, Brazil, USA and Korea. Study objects of bamboo species in various countries have notable local characteristics. Therefore, scientists usually choose special bamboo species with domestic characteristics for study.
A kind of herbaceous bamboo in Subgen. Sasamorpha, Subgen. Sasa and Sasa Makino et shbata (i.e. Sasa albomarginta Makino & Shibata in Latin or bamboo grass in English) has been systematically studied and a series of national patents have been filed in Japan since 1970s. A few of researches related to bamboo species in Phyllostachys after 1990. For example, the extract of tender stems of bamboo in Phyllostachys, which is obtained by solvent extraction, can be added into the feed for animals such as poultry, livestock, shellfish, pets and experimental animals, etc (Wataru, S. Healthful feed containing bamboo extract, JP. Pat. 57,074,049, filed in 1980). In another patent application filed in 1980 (Healthful feed containing bamboo extract, JP. 57,039,753), it was disclosed that the fragmentized tender stems of bamboo in Phyllostachys were extracted 2 weeks by methanol, ethanol, chloroform, benzene or hot water under the normal temperature, or they were put into containers, heated up to 180° C. by steams, cooled after distillation, so that a mixture of essential oil and water was produced. Said concentrated products under decompression can be added into various foods. Besides, the bamboo extract obtained by dry or steam distillation has a therapeutic effect on hemorrhoids. Different active portions separated by silica gel column have different healthy effects such as hemorrhoids therapy, anti-hypertension and relaxation. Furthermore, the hemorrhoids therapeutic portion has prominent effects when orally or topically administrated (Wataru, S. Production of bamboo extract having effect for hemorrhoids, JP. Pat. 1982, No. 57,038,721).
It has been reported that the extract of bamboo leaves and its lignin have anti-tumor activities (Kuboyama, N. et al. Anti-tumor activity of bamboo leaf extracts, JPN J. Pharmacol., 1979, 29(SUPPL.): 170; Anti-tumor activities of bamboo leaf extracts and its lignin, Folia Pharmacol. JPN, 1981, 77(6): 579-596). Besides, the extract solution of bamboo leaves was used in periodontal therapy (Sato, T. et al. The use in periodontal therapy of a bamboo leaf extract solution, Nippon Shishubyo Gakkai Kaishi, 1986, 28(2): 752-757). The effective compositions extracted from bamboo in Phyllostachys such as P. bambusoides, P. pubescens and P. nigra var. henonis. can inhibit the growth of poly-dandruff fungus and the lipid peroxidation, prevent the skin aging process and stabilize products (Kenji, M. et al. Skin, scalp and hair agent containing component of suppressing growth of dandruff fungus extracted from bamboo, JP. Pat. 1991, No. 3,251,518). Therefore, many different kinds of bamboo extracts have been studied and applied in many fields, such as the identification of the anti-microbial active component of 2,6-dimethoxyl p-benzoquinone, the preparation of deodorant, the application of anti-microbial activity and the exploitation of meat additives, etc (Nishina, A. et al. J. Agric. & Food Chem., 1991, 39(2): 266-269; Takatoshi, K. JP. Pat. 9,094,290; Yamanaka, Satoshi. et al. Anti-microbial activity of bamboo dry distillate and its application, Gekkan Fudo Kemikaru, 1998, 14(9): 57-60; Akimitsu, M. JP. Pat. 11,346,719). The anti-oxidative activity of tricin and taxifolin, which are two kinds of anti-oxidative compounds extracted from bamboo shoot sheath, approximately corresponds to 10% and 1% of that of α-tocopherol, respectively (Sakai, K. Isolation of antioxidative compounds from bamboo shoots sheath, Nippon Shokuhin Kagaku Kaishi, 1999, 46(7): 491-493).
China is praised as “Bamboo Kingdom”. Bamboo not only has centuries-old edible history in China (C. S. Hu et al. Development history of bamboo as medicine and food, Journal of Bamboo Research, 1999, 18(1): 27-31), but also is a kind of important resource on the exploitation of Chinese medicine and health food. Therefore, it has an important significance in the modernization of Chinese medicine. In China Chinese Medicine Resource Highlights, there are 32 species of bamboo in 10 genera among 12,694-recorded kinds of Chinese medicine, while there are about 5 species of bamboo plants in Pharmacopoeia of the P. R. China (1990 Edition). Different parts of bamboo, such as bamboo leaf, bamboo rhizome system, Caulis bambusae in Taeniam (bamboo shavings), Succus bambusae (bamboo juice), Fructas bambusae (bamboo fruit), bamboo poles, Concretionsilicea bambusae (concretionin bamboo stem), Shiraia bambusicola Henn. (tabasheer), bamboo shoots, Amomum villosum bambusae, Omphalia lapidescens schroet, membranae bambusae (mambranein bamboo stem), bamboo essence, Rhizomys sinensis Gray. and Xylocopadis similis Lep., have different therapeutic effects (Z. Y. Zhang et al. Potential of bamboo on the exploitation of Chinese Medicine and health food, Modernization of Traditional Chinese Medicine, 2000, 2(3): 54-56).
Abundant researches on bamboo components and bioavailability have been studied in China. Furthermore, bamboo-leaf flavonoids have been studied systematically and thoroughly by applicant of the invention. Recently, the extract of bamboo leaves (Ebl971), a kind of natural bioflavone product that is extracted from the most abundant bamboo species (i.e. Phyllostachys Sieb. et Zucc.) in domestic bamboo resources, has been exploited by applicant. This natural product mainly contains four kinds of C-glycosyl flavones, i.e. orientin, homoorientin, vitexin and isovitexin (Y. Zhang. Natural functional extract of bamboo leaves: bamboo leaf anthoxanthin, China Food Additives, 2002, (3): 54-58, 66). Ebl971 has many kinds of biological effects such as anti-free radical, anti-oxidation, anti-senescence, anti-bacteria, anti-virus and preventing cardiovascular and cerebrovascular disorders and senile degenerative diseases, etc (Y. Zhang et al. Studies on antioxidative fraction in bamboo leaves and its capacity to scavenge active oxygen radicals, Journal of Bamboo Research, 1996, 15(3): 17-24; Y. Zhang et al. Experimental studies on anti-aging effect of the leaf-extract of P. nigra var. henonis, Journal of Bamboo Research, 1997, 16(4): 62-67; Y. Zhang. Determination of SOD-like activity of bamboo leaf extract by pyrogallol autooxidation, Food Science, 1997, 18(5): 47-49; Y. Zhang et al. The bio-antioxidative activity of functional factors in bamboo leaves, in: Proceedings of the 3rd International Conference of Food Science and Technology, Oct. 19-23, 1997, Davis, U.S. Ed. Whitaker, J. R. Food and Nutrition Press, 1998, pp 266-273; Y. Zhang. Comprehensive study on SOD-like activity of bamboo leaf extract, Journal of Chinese Institute of Food Science and Technology, 1998, 2(2): 62-66; Y. Zhang et al. Study on the relationship between the structure of flavonoids and their scavenging capacity on active oxygen radicals by means of chemiluminescence, Natural Product Research and Development, 1998, 10(4): 26-33; Y. Zhang et al. The bio-antioxidative activity of functional factors in bamboo leaves, Acta Nutrimenta Sinica, 1998, 20(3): 367-371; C. Hu, Y. Zhang and Davis D. K. Evaluation of antioxidant and prooxidant activities of bamboo Phyllostachys nigra var. henonis leaf extract in vitro, J. Agric. Food Chem., 2000, 48(8): 3170-3176). Ebl971 has abundant material resources, definite functional factors, good edible safety (actually no toxicity), high efficient and stable preparation quality (water-, heat- and acid-resistance, etc) and fresh and sweet bamboo flavor so that it has made a figure in the field of natural functional food additives and medical health food recently. Furthermore, China Patent Office issued two patents for invention to applicants in 2000 and 2001, respectively (Y. Zhang. The production method of flavonoid extract and powder extracted from bamboo, CN. Pat. ZL 98 1 04564.2; Y. Zhang. A kind of health beer fortified by the bamboo extract-leaf-flavonoids, CN. Pat. ZL 98 1 04563.4). Nearly all the bamboo researches in China are aimed at Phyllostachys Sieb. et Zucc., especially P. nigra var. henonis, P. pubescens and P. bambusoides Sieb. et Zucc.
Bamboo researches in India relate to nutrition of bamboo fruits, processing of bamboo shoots, manufacture of bamboo fibers and feed application of bamboo leaves. The objects of these researches mainly relate to bamboo species in Bambusa and Dendrocalamus genus with local resource characteristics.
Brazil locates in bamboo zones of South America. The main species of bamboo in Brazil are cluster bamboo in Bambusa and Dendrocalamus genus. Brazilian scientists have ever detected carcinogenic compounds from Dendrocalamus giganteus Munro. Nevertheless, they can be removed by different kinds of processing methods (Ferreira, V. L. P. et al. Elimination of cyanogenic compounds of bamboo shoots Dendrocalamus giganteus Munro by different processes, Rev Esp Cienc Tecnol Alimentos, 1992, 32(2): 175-184).
There is nearly no bamboo in the main land of U.S. However, with the continuous cognition of healthy effects of bamboo products, some research institutes began the research on bamboo products such as bamboo shoots. The department of food and nutrition in Purdue University reported the effect on lowering serum cholesterol level in rats by bamboo shoots in the U.S. Federal Conference of Experimental biology (Anaheim, Calif., U.S.) (Story, J. A. et al. Bamboo shoots lower serum cholesterol in rats, FASEB (Fed Am Soc Exp Biol) J, 1992, 6(5): A1653). Furthermore, the systematic research on the hypocholestolemic effect of bamboo shoots both in vivo and in vitro by He in Rutgers University has suggested that phytosterols play a key role in this effect (Y. H. He. The hypocholestolemic effect of bamboo shoots in vivo and in vitro (Phyllostachys edulis, Phytosterols), Dr. Paper of Rutgers University, 1998).
It can be inferred from bamboo extract researches all over the world that the extraction methods of bamboo mainly relate to water extraction, organic solvent extraction and steam distillation. However, studies on the chemical research of active compositions and the structure relationship between compositions and their physiological and pharmacological activity are extremely limited.
The plant resources of this invention relate generally to complete bamboo stools, including stems, roots, leaves, branches and shoots, but mainly relate to bamboo bark the obtained portion of which is similar with bamboo shavings recorded in Dictionary of Traditional Chinese Medicine (Vol. 1, China Medical Science and Technology Press, 1993, pp 2137-2139). Furthermore, the source and extent of bamboo species in the invention are also similar to those recorded in this dictionary, especially the bamboo in Phyllostachys Sieb. et Zucc.
Bamboo shavings recorded in Dictionary of Traditional Chinese Medicine (Syn. with bamboo bark recorded in Synopsis Prescriptions of the Golden Chamber, green bamboo shavings recorded in Divine Husbandman's Classic of Materia Medica, bamboo bark in P. nigra var. henonis recorded in Divergent Records, bamboo shavings in P. nigra var. henonis recorded in Materia Medica of Food Therapy, Ma ba recorded in Herb Prescriptions or inferior outer of bamboo recorded in Shanghai Service Chinese Herb Medicine) are external or intermediate layers of some bamboo stems of Phyllostachys, Bambusa or Dendrocalamus genus in Gramineae. Certified products of bamboo shavings can be divided into two categories, Phyllostachys nigra var. henonis (Bean) Stapf. (P. henryi Rendle) and Phyllostachys aurea Carr. ex A. and C. Riviere. Furthermore, many other kinds of bamboo also can be used as sources of bamboo shavings such as P. glauca McClure, P. makinoi Hayata, P. nidularia Munro, P. viridis (Young) McClure, Bambusa tuldoides Munro, B. pervariabilis McClure, B. chungii McClure [Lingnania chungii (McClure) McClure], Dendroclamopsis beecheyana (Munro) Keng f. var. pubescens (P. F. Li) Keng (Sinocalamus beecheyana var. pubescens P. F. Li) and Dendrocalamus affinis Rendle (Sinocalamus affinis (Rendle) McClure). On one hand, it can be inferred from bamboo distributions in China that the bamboo species distributed in Yangtze River Basin are mainly P. nigra var. henonis, a kind of scattered bamboo, and the following P. aurea Carr. ex A. & C. Riviere, P. makinoi Hayata, P. nidularia Munro, P. glauca McClure and P. viridis (Young) McClure, etc. On the other hand, the bamboo species distributed in Southwest and South Region of China are mainly B. tuldoides Munro, a kind of cluster bamboo, and the following Sinocalamus beecheyana var. pubescens P. F. Li, B. chungii McClure, B. pervariabilis McClure and Sinocalamus affinis McClure (Dendrocalamus affinis Rendle), etc.
Bamboo shavings, which act as a kind of clinical Chinese traditional medicine, have mainly been used in many symptoms such as gastropyretic vomiting and chest diaphragm annoyance, etc. Traditional roasting and preparing method of bamboo shavings is to remove impurities and cut it into segments or kneading agglomerate. They can be prepared after ginger juice stir-frying. This method is initially recorded in Divine Husbandman's Classic of Materia Medica and the efficacy has been recorded in materia medica of past dynasties. Examples are showed as follows: (i) Bamboo shavings can be used to treat many symptoms such as over-stained relapse of exogenous febrile disease, infantile middle laryngeal abscess and female excessive fetal movement (S. Z. Li, Detailed Outline of Materia Medica). (ii) Bamboo shavings especially eliminate stomach heat and can be prescribed for deficient restlessness with polydipsia, gastric asthenia with vomiting, hiccup with bloody sputum and puerperal deficient restlessness (L. Zhang, Journey to Source of Materia Medica). (iii) Bamboo bark bolus can be prescribed for puerperal deficient restlessness with vomiting (Z. J. Zhang, Synopsis Prescriptions of the Golden Chamber). (iv) Sweet soup of bamboo shavings can be prescribed for puerperal endoasthenia and dysphoric fever with short breath in order to calm the middle (stomach and spleen) while mild soup of them can be used to puerperal deficient restlessness with headache, short breath and annoyance in order to cool stomach. Although the character of soup is sweet and slippery, it can promote defecation and urination so that nothing can be anxious about including exogenous pathogen (S. M. Sun, Prescriptions worth a Thousand Gold). (v) Bamboo shavings, which are dispersing herbs eliminating sthenia, cooling herbs eliminating heat or bitter herbs keeping the adverse energy downwards, are good prescriptions of eliminating pyretic cough and expelling stagnation. They can be mainly prescribed for cholic and gastric phlegmatic fever symptoms such as gastropyretic dysphagia, gastrasthenia retching, pyretic hiccup, phlegmatic fever with nausea, alcoholic injury vomiting, phlegmatic acid saliva, terrified and severe palpitation, cardiac restlessness and sleep dysphoria (S. X. Jia, Medicinal Ingredients Changes and Corrections). (vi) Bamboo shavings with a sweet, mild taste and a cold, slippery odor can be prescribed for many symptoms such as polydipsia restlessness, dysphagia with vomiting, pernicious vomiting, haematemesis and non-traumatic hemorrhage caused by pulmonary heat accumulation and nourishing loss involving lung meridian (G. X. Huang, Truthseeking Materia Medica).
Pharmacopoeia of the P. R. China (2002 Edition) declares that bamboo shavings originate from Phyllostachys nigra (Lodd.) Munro var. henonis (Mitf.) Stapf ex Rendle, Bambusa tuldoides Munro and Sinocalamus beecheyanus (Munro) McClure var. pubescens P. F. Li with a sweet-natured taste, a cold odor, lung distribution and stomach meridian. Bamboo shavings mainly can be prescribed for eliminating phlegm by cooling and eliminating dysphoria with stopping emesis. Furthermore, they can be used to treat the following symptoms: pyretic cough, gallbladder fire with sputum, dysphoric fever with vomiting, terrified palpitation with insomnia, apoplexy with phlegmatic coma, aphasia with stiff tongue, gastropyretic vomiting, pregnant pernicious vomiting and excessive fetal movement. However, the pharmacological details of Bamboo shavings are still unknown and the materials of functional evaluation are relatively absent because the componential and pharmacological study on bamboo shavings is seldom carried out in the traditional Chinese medicine. Although Dictionary of Traditional Chinese Medicine refers to some components in bamboo shavings that have inhibitory effects on cAMP phosphodiesterase (China Medical Science & Technology Press, Vol. 1, pp 2138), and they are identified as 2,5-dimethoxy-p-benzoquinone, p-hydroxybenzoaldehyde and syringaaldehyde. No documents have reported triterpenoids in bamboo shavings so far.
Nevertheless, the composition descriptions of Herba Loophatheri (Common Lopatherum Herb) in Chinese folk records relate to triterpenoids. However, this kind of Herba Loophatheri is the stem and leaf of Lophatherum gracile Brongn in Gramineae, which is a herbaceous perennid but doesn't belong to Bambusoideae family. It is cultivated in Zhejiang, Jiangsu, Hunan and Hubei Province in China. This kind of herb has the efficacy of eliminating dysphoria by cooling and promoting fluid production to induce diuresis with a sweet and mild taste, a cold odor and heart and kidney meridian. Furthermore, it can be used to treat many symptoms such as febrile polydipsia, hot urination, turbid stranguria, aphthous stomatitis and tongue abscess and gingival cyst. The stems and leaves of Lophatherum gracile Brongn mainly contain triterpenoids and sterols which are identified as arundoin, cylindrin, taraxerol, friedelin, β-sitosterol, stigmasterol, campesterol and taraxasterol while their aerial parts contain phenols, amino acids, organic acids and saccharides. Recently, Q. Chen conducted a systematic studies on the components of Lophatherum gracile Brongn. (Q. Chen et al. Chemical studies on the constituents of Lophatherum gracile Brongn., J. Shenyang Pharmaceutical Univ., 2002, 19 (1): 23-24). Eight compounds were identified as 4-hydroxy-3,5-dimethoxybenzaldehyde, trans-p-hydroxy cinnamic acid, tricin, tricin-7-O-β-D-glucosyl, vitexin, thymine, vanillic acid and adenine. Unfortunately, triterpenoids were not reported.
Most triterpenoids, which consist of 30 carbons, are considered a condensation compound of 6 isoprenes. Triterpenoids and their saponins, which are important biological active components in natural kingdom, can be divided into two categories, i.e., triterpenoid saponins and steroid saponins, according to their different chemical structures. Many kinds of triterpenoid saponins extracted from several important Chinese herbal medicine such as Panax genseng, Panax notoginseng, Gynostemma pentaphyllum, Bupleurum, Astragalus, Polygala temuifolia, Phytolacca acinosa, Platycodon grandiflorum and Anemarrhena asphodeloides have been studied systematically with the continuous advance in study methods of organic compounds in recent 30 years. Their biological activities and medicinal values have been recognized increasingly. These substances have many kinds of biological activities such as anti-bacteria, anti-virus, anti-tumor, anti-fertility, anti-inflammatory, anti-hyperlipidemia, anti-hypertension, anti-hyperglycemia and immunoregulation, etc. Further, triterpenoids have physiological activities in the cardiovascular system, nervous system, adrenal cortex system and enzymatic activity so that they have become an important investigated subject in the research of natural medicine (X. S. Yao. Natural Pharmaceutical Chemistry (3rd Edition), People's Medical Publishing House, 2001, 257-294; S. J. Wu et al. Recent research survey on pharmacological activities of saponins, World Notes on Phytopharmacy, 1994, 9(6): 246-252).
Generally, the number of pentacyclic triterpenoids is more than any other kinds of triterpenoids. They are mainly divided into the following four categories: oleanane, ursane, lupinane and friedelane. Among them, friedelane is derived from the translocation of oleanen hydroxymethyl group. Tripterygium wilfordii, which belongs to Celastraceae family, has a centuries-old history of folk pharmaceutical products in China. Recently, it has been widely applied in the clinic, especially in rheumatoid diseases because of its unique therapeutic effectiveness. Meanwhile, several kinds of triterpenoids including friedelane triterpenoids have been extracted from Tripterygium wilfordii. For instance, triptergone, a kind of triterpenoid extracted from the peeled root center of Tripterygium wilfordii, is a friedelane derivative without methyl group on position 25 and its chemical name is 3-hydroxy-25-nor-friedel-3,1(10)-dien-2-one-30-oic acid. More than 20 kinds of friedelane compounds or their degradation products have been extracted from Kokona zeylanica in Celastraceae family so far. Meanwhile, 11 compounds have been obtained from the stem bark of this plant and identified as friedel-3-one compounds by Leslie et al.
The extraction and separation method of triterpenoids can be generally divided into four categories: (i) The extraction is extracted by ethanol or methanol and triterpenoids are directly separated. (ii) The extraction is primarily extracted by alcohol solvents and divisionally extracted by petroleum ether, chloroform and acetic ester in turn and further separated. The triterpenoid compositions are mainly obtained from chloroform. (iii) Triterpenoids are separated by the preparation of derivatives. In other words, the extraction is extracted by ether, methylated by diazomethane and prepared as methyl ester derivatives, or it is prepared as acetyl derivatives by conventional acetylation and further separated. (iv) Triterpenoids are prepared after triterpenoid saponins hydrolyzation because many kinds of triterpenoids is present as saponins in plant materials. In other words, triterpenoid saponins are hydrolyzed and the hydrolysis products are extracted by organic solvents such as chloroform. Finally, triterpenoids are prepared. However, the extraction method of chemical solvents has many defects such as long operation, great solvent consumption and bad operational environment. Furthermore, the extract obtained by organic solvent extraction has unstable product quality, high contents of heavy metal and pesticide residue and low extraction yield.